This invention relates generally to classification or sorting apparatuses for articles such as coins and more particularly to a sorting device for selectively separating, by the kind of coin, coins of different diameters of two or more kinds.
Heretofore, in a device for sorting coins of different diameters of several kinds into groups each of the same kind, sorting holes having different widths for receiving coins according to the kind of coin are ordinarily arranged in a coin passage in sequence from a hole for the smallest diameter to a hole for the largest diameter. A mixture of coins of different kinds are fed into this passage and are caused to drop in sequence through the respectively corresponding holes thereby to be sorted by kind.
In a sorting device of the above described arrangement, however, during the feeding of the coins, the coins will not drop through their respective sorting holes unless they travel accurately in centerline alinement with these holes. For this reason, there has been the possiblity in a sorting device of this character of coins passing by the sorting holes through which they should drop, thereby giving rise to erroneous sorting and a lowering of the sorting accuracy. The same problem has been present also in sorting devices of the type wherein only coins of a specific kind are passed, and coins of other kinds are discharged at intermediate points of their travel.
Therefore, one expedient resorted to heretofore for assuring that coins being sorted will drop positively into their proper holes even when the coins are fed along the coin passage with some lateral misalinement or offset from the hole centerline has been to lengthen the sorting holes to lengthen the time of passing of the coins over the holes and thereby to facilitate the dropping of the coins. When this is done, however, the total length of the coin passage of the apparatus becomes long, and the entire apparatus tends to become large.
On one hand, there are coin sorting devices of a type wherein the coin passage is laterally inclined to cause the coins to travel through the passage in a state in which they are constantly in contact with one side wall of the passage and thereby to assure positive dropping of the coins into the proper holes. In this device, however, the friction of the coins relative to the side wall surface of the coin passage increases, whereby slippage readily occurs between an endless propelling belt propelling the coins and the coins. As a consequence, positive propelling of the coins is difficult, and, at the same time, the wear of the coins becomes a serious problem.
Furthermore, as mentioned hereinabove, there is a sorting device having a coin feeding passage for passing only coins of one specific kind, for example, and feeding these coins to the packaging of section of a coin packaging machine. This coin feeding passage also has problems similar to those described above in the sorting of small-diameter coins of different kinds througb sorting holes for discharging small-diameter coins provided in the coin passage.
More specifically, in the case of a conventional coin passage, an endless propelling belt is provided above and along the passage and propels the coins along the passage as it presses downward on the upper surfaces of the coins. This propelling belt is passed around pulleys provided at the entrance and exit ends of the coin passage. When a thick coin enters the space between the belt and the passage at the position of a pulley, the pulley "gives" or retreats upward to absorb the increased coin thickness. For this reason, when a thick coin thus enters at the position of the pulley, the lower span of the belt for contacting the coins is raised and separates from the coins at regions below the belt intermediate between its ends, or the belt contact pressure relative to these coins is reduced, whereby these coins are no longer driven. This has heretofore been a troublesome problem.